Climatic extremes can be as significant as averages in setting the conditions for successful organismal function and in determining the distribution of different forms. For lightweight, flexible ...structures such as leaves, even extremes lasting a few seconds can matter. The present review considers two extreme situations that may pose existential risks. Broad leaves heat rapidly when ambient air flows drop below c. 0.5 m s⁻¹. Devices implicated in minimizing heating include: reduction in size, lobing, and adjustments of orientation to improve convective cooling; low near-infrared absorptivity; and thickening for short-term heat storage. Different features become relevant when storm gusts threaten to tear leaves and uproot trees with leaf-level winds of 20 m s⁻¹ or more. Both individual leaves and clusters may curl into low-drag, stable cones and cylinders, facilitated by particular blade shapes, petioles that twist readily, and sufficient low-speed instability to initiate reconfiguration. While such factors may have implications in many areas, remarkably little relevant experimental work has addressed them.
The applications of Förster resonance energy transfer (FRET) grow with each year. However, different FRET techniques are not applied consistently, nor are results uniformly presented, which makes ...implementing and reproducing FRET experiments challenging. We discuss important considerations for designing and evaluating ensemble FRET experiments. Alongside a primer on FRET basics, we provide guidelines for making experimental design choices such as the donor-acceptor pair, instrumentation and labeling chemistries; selecting control experiments to unambiguously demonstrate FRET and validate that the experiments provide meaningful data about the biomolecular process in question; analyzing raw data and assessing the results; and reporting data and experimental details in a manner that easily allows for reproducibility. Some considerations are also given for FRET assays and FRET imaging, especially with fluorescent proteins. Our goal is to motivate and empower all biologists to consider FRET for the powerful research tool it can be.
Environmentalism, in theory and practice, is concerned with protecting nature. But if we have now reached "the end of nature," as Bill McKibben and other environmental thinkers have declared, what is ...there left to protect? InThinking like a Mall, Steven Vogel argues that environmental thinking would be better off if it dropped the concept of "nature" altogether and spoke instead of the "environment" -- that is, the world that actually surrounds us, which is always abuiltworld, the only one that we inhabit. We need to think not so much like a mountain (as Aldo Leopold urged) as like a mall. Shopping malls, too, are part of the environment and deserve as much serious consideration from environmental thinkers as do mountains. Vogel argues provocatively that environmental philosophy, in its ethics, should no longer draw a distinction between the natural and the artificial and, in its politics, should abandon the idea that something beyond human practices (such as "nature") can serve as a standard determining what those practices ought to be. The appeal to nature distinct from the built environment, he contends, may be not merely unhelpful to environmental thinking but in itself harmful to that thinking. The question for environmental philosophy is not "how can we save nature?" but rather "what environment should we inhabit, and what practices should we engage in to help build it?"
Both a landmark text and reference book, Steven Vogel's Life in Moving Fluids has also played a catalytic role in research involving the applications of fluid mechanics to biology. In this revised ...edition, Vogel continues to combine humor and clear explanations as he addresses biologists and general readers interested in biological fluid mechanics, offering updates on the field over the last dozen years and expanding the coverage of the biological literature. His discussion of the relationship between fluid flow and biological design now includes sections on jet propulsion, biological pumps, swimming, blood flow, and surface waves, and on acceleration reaction and Murray's law. This edition contains an extensive bibliography for readers interested in designing their own experiments.
This essay conceptualizes market governance as a balance of power and discusses the implications for current debates over antitrust policy. This framework offers a way to interpret and evaluate the ...“neo-Brandeisian” school that views concentrated market power as a threat to democracy as well as to economic goals, such as productivity and innovation. It suggests that the government can deploy antitrust policy to alter the balance of power to promote the public welfare without necessarily impeding competition or otherwise distorting markets. And antitrust policies that constrain market power can have the double benefit of making both markets and politics more competitive.
The basal ganglia are subcortical nuclei that control voluntary actions, and they are affected by a number of debilitating neurological disorders. The prevailing model of basal ganglia function ...proposes that two orthogonal projection circuits originating from distinct populations of spiny projection neurons (SPNs) in the striatum--the so-called direct and indirect pathways--have opposing effects on movement: activity of direct-pathway SPNs is thought to facilitate movement, whereas activity of indirect-pathway SPNs is presumed to inhibit movement. This model has been difficult to test owing to the lack of methods to selectively measure the activity of direct- and indirect-pathway SPNs in freely moving animals. Here we develop a novel in vivo method to specifically measure direct- and indirect-pathway SPN activity, using Cre-dependent viral expression of the genetically encoded calcium indicator (GECI) GCaMP3 in the dorsal striatum of D1-Cre (direct-pathway-specific) and A2A-Cre (indirect-pathway-specific) mice. Using fibre optics and time-correlated single-photon counting (TCSPC) in mice performing an operant task, we observed transient increases in neural activity in both direct- and indirect-pathway SPNs when animals initiated actions, but not when they were inactive. Concurrent activation of SPNs from both pathways in one hemisphere preceded the initiation of contraversive movements and predicted the occurrence of specific movements within 500 ms. These observations challenge the classical view of basal ganglia function and may have implications for understanding the origin of motor symptoms in basal ganglia disorders.
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This entertaining and informative book describes how living things bump up against non-biological reality. "My immodest aim," says the author, "is to change how you view your immediate surroundings." ...He asks us to wonder about the design of plants and animals around us: why a fish swims more rapidly than a duck can paddle, why healthy trees more commonly uproot than break, how a shark manages with such a flimsy skeleton, or how a mouse can easily survive a fall onto any surface from any height.
The book will not only fascinate the general reader but will also serve as an introductory survey of biomechanics. On one hand, organisms cannot alter the earth's gravity, the properties of water, the compressibility of air, or the behavior of diffusing molecules. On the other, such physical factors form both constraints with which the evolutionary process must contend and opportunities upon which it might capitalize. Life's Devices includes examples from every major group of animals and plants, with references to recent work, with illustrative problems, and with suggestions of experiments that need only common household materials.
Could international financial capital impose shareholder sovereignty on Japan, the ultimate bastion of stakeholder capitalism? As the Japanese economy descended from boom to bust in the early 1990s, ...government and industry leaders called for a decisive move toward US-style shareholder capitalism, and increasing foreign share ownership exerted strong pressure to adapt corporate governance practices to Anglo-American norms. In practice, however, the government gave firms more options for restructuring but did not make them more beholden to shareholders. Firms on their part favored superficial adjustments to prop up share prices rather than fundamental changes, because they sought to preserve the strengths of their traditional business models. This article explains how marketplace developments, domestic political dynamics, and corporate strategies combined to produce the distinctive pattern of Japanese corporate governance reforms since the 1990s. It concludes with an assessment of the consequences of these reforms for managers, workers, shareholders, and the general public.
Life's Devices Vogel, Steven
2020, 1988, 2020-03-31
eBook
This entertaining and informative book describes how living things bump up against non-biological reality. "My immodest aim, " says the author, "is to change how you view your immediate ...surroundings." He asks us to wonder about the design of plants and animals around us: why a fish swims more rapidly than a duck can paddle, why healthy trees more commonly uproot than break, how a shark manages with such a flimsy skeleton, or how a mouse can easily survive a fall onto any surface from any height. The book will not only fascinate the general reader but will also serve as an introductory survey of biomechanics. On one hand, organisms cannot alter the earth's gravity, the properties of water, the compressibility of air, or the behavior of diffusing molecules. On the other, such physical factors form both constraints with which the evolutionary process must contend and opportunities upon which it might capitalize. Life's Devices includes examples from every major group of animals and plants, with references to recent work, with illustrative problems, and with suggestions of experiments that need only common household materials.
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